1. Technical Field
The present disclosure relates to a circuit, and more particularly to a circuit for the testing of inrush current.
2. Description of Related Art
Inrush current, or input surge current, refers to the maximum, instantaneous input current drawn by an electrical device when first turned on. For example, at the moment a computer is powered on, a power supply of the computer incurs high inrush currents until it is fully powered up. If the inrush current is too great, the power supply is easily damaged. Thus, the power supply needs to be tested before being used within the computer.
The tester often uses a public alternating current (AC) source as the test electrical source. However, the public AC current may be unstable and variable, and the measurement of the magnitude of the tested inrush current not reliable. In this situation, the tester may not be sure whether the power supply meets performance standards. The tester must repeatedly test the power supply to be sure it can withstand the inrush current without damage. This is a time-consuming and imprecise procedure.
Furthermore, the tester often uses a switch with a movable contact connected between the AC source and the power supply. The movable contact easily rusted, and the inrush current may be disturbed, which can throw of the test results.
What is needed, therefore, is a circuit for testing the inrush current more precisely and without costly repetition.